Lithium battery

ABSTRACT

The present invention relates to a lithium battery and, more particularly, to a lithium battery, in which the structure of a battery module contained in the lithium battery is simplified, thus reducing the size of the entire lithium battery, and which includes a connector by which two or more lithium batteries are mechanically coupled to each other so that in response to a required amount of power, an appropriate number of lithium batteries can be easily connected to each other.

CROSS-REFERENCE TO RELATED APPLICATION AND CLAIM OF PRIORITY

This application is a divisional application of application Ser. No.13/526,636, filed on Jun. 19, 2012, which claims priority to KoreanPatent Application Nos. 10-2012-0020041, filed on Feb. 28, 2012, and10-2012-0020187, filed on Feb. 28, 2012, which are incorporated hereinby reference in their entirety.

BACKGROUND

1. Field of the Invention

The present invention relates generally to lithium batteries.

2. Description of the Related Art

Secondary batteries are batteries which are designed to be recharged andused multiple times, unlike primary batteries. Recently, a lot ofresearch into such secondary batteries being conducted along withdevelopment of high technology fields related to, for example, digitalcameras, cellular phones, notebook computers, hybrid vehicles, etc.Nickel-cadmium batteries, nickel-metal hydride batteries, lithiumsecondary batteries, etc. are representative examples of the secondarybatteries. Among such examples, the operating voltage of the lithiumsecondary batteries (hereinafter, referred to as ‘lithium batteries’)ranges from 2.0 V to 4.2 V or may be higher. Such a lithium battery maybe typically used as a power supply for mobile electronic devices, or aplurality of lithium batteries may be connected in series to each otherand used in a high power hybrid vehicle. The operating voltage of thelithium batteries is three times greater than that of nickel-cadmiumbatteries or nickel-metal hydride batteries. The energy density per unitweight of the lithium batteries is also comparatively high. Therefore,the use of the lithium batteries is rapidly increasing.

Such a lithium battery includes a bare cell which includes battery tabsthrough which power is input or output, and a case in which the barecell is housed. Here, the bare cell that is housed in the case is calleda battery cell.

The battery cell includes a pouch type bare cell and a battery cellcase. The battery cell case includes a front case plate and a rear caseplate which are disposed on front and rear surfaces of the bare cell andare separably coupled to each other to protect the bare cell.

In conventional battery cell cases, a front case plate and a rear caseplate are made of metal or adiabatic plastic and are coupled to eachother while in close contact with the front and rear surface of a barecell. The front and rear case plates are fastened to each other byscrews or bolts after having been put in close contact with each other.

As such in the case of the conventional battery cell cases, the processof fastening the front case plate to the rear case plate includesinserting bolts or screws into the front and rear case plates andtightening the bolts or screws using a tool, such as a screwdriver orwrench. Therefore, the working time required to assemble the batterycell case is increased, thus reducing productivity.

Furthermore, in the case of a lithium battery using the conventionalbattery cell, typically, a plurality of battery cells are contained in asingle case and are connected in series or parallel to each other, thusforming a medium-large sized lithium battery that can be used as ahigh-voltage power supply in an industrial site.

The medium-large sized lithium battery generally includes ten or morebattery cells that are electrically connected to each other. Suchmedium-large sized lithium batteries have been used in places whereindustrial or large-capacity power is needed. On the other hand, in thecase of a lithium battery for domestic or portable use, two to tenbattery cells are typically connected in series or parallel to eachother.

As such, the conventional lithium batteries can be electricallyconnected to each other to produce a required amount of power. However,the connection between the lithium batteries is just an electricalconnection in which the lithium batteries are mechanically separatedfrom each other. Therefore, accidents caused by negligence may occur atindustrial sites, and it may become an inconvenience for pedestrians.

Moreover, in the conventional lithium battery having one or more barecells, a comparative large volume case that houses each bare cellincreases the size of the entire lithium battery. The greater thecapacity of the lithium battery is, the larger is the size of the entirelithium battery. Therefore, it is very inconvenient to transfer or storethe lithium battery.

SUMMARY

According to an aspect of the present invention, lithium batteries eachof which contains two or more battery cells can be mechanicallyconnected to each other, thus ensuring that the use of the lithiumbatteries is safe.

Another aspect of the present invention is to provide a lithium batteryin which cases that house the bare cells can be coupled to each other inan insert coupling manner without using a separate locking member orfastening device, thus reducing the size of the entire lithium battery.

A further aspect of the present invention is to provide a lithiumbattery which is configured such that the lithium battery containing atleast one battery cell can be coupled to another lithium battery withoutusing a separate locking member or fastening device, thus reducing thenumber of elements, thereby reducing the size of the entire lithiumbattery assembly including the lithium batteries.

In an embodiment of the present invention, a lithium battery includes: abattery module having battery cells electrically connected to each othersuch that power of different poles is input into or output from thebattery cells; an upper plate member forming an upper surface of thelithium battery, the upper plate member covering an upper end of thebattery module contained in the lithium battery; a lower plate memberforming a bottom plate of a space that contains the battery moduletherein; side plate members including a pair of side plate bodiesprovided at positions spaced apart from each other to form opposite sidesurfaces of the lithium battery, the side plate bodies being coupled atupper and lower ends thereof to the lower plate member and the upperplate member; and end plate members coupled to front and rear ends ofthe side plate members to form front and rear surfaces of the lithiumbattery, wherein either of the pair of side plate bodies of the sideplate members includes a connection plate extending therefrom in onedirection, with a connection protrusion protruding downwards from alower surface of the connection plate, and a remaining one of the pairof side plate bodies has a connection depression into which a connectionplate of another lithium battery is able to be seated.

In an embodiment, the upper plate member may have: an upper depressionformed in a vertical extension panel extending downwards from a topsurface of the upper plate member so that the connection depression isopen upwards through the upper depression; and an upper locking slotformed in each of opposite end surfaces of the vertical extension panel.

In an embodiment, each of the end plate members may include: an endplate body provided upright and inserted into each of front and rearends of the pair of side plate members; at least one first insertprotrusion protruding upwards from an upper end of the end plate body; afirst locking protrusion protruding upwards from the upper end of theend plate body, with a hook provided on an end of the first lockingprotrusion, the hook of the first locking protrusion being locked to thecorresponding upper locking slot; at least one second insert protrusionprotruding downwards from a lower end of the end plate body; and asecond locking protrusion protruding upwards from the lower end of theend plate body, with a hook provided on an end of the second lockingprotrusion, the hook of the second locking protrusion being locked tothe lower plate member.

In an embodiment, the lower plate member may include: a bottom plate onwhich the battery module is placed; bottom side panels protrudingupwards on opposite side edges of the bottom plate, each of the bottomside panels having a stepped portion on an inner surface thereof so thatthe lower end of the corresponding side plate body is inserted insidethe inner surface of the bottom side panel and seated onto the steppedportion; and bottom end panels protruding upwards from front and rearends of the bottom plate, each of the bottom end panels having a lowerlocking slot to which the corresponding second locking protrusion islocked.

In an embodiment, each of the side plate members may include: a firstinsert plate provided and stepped on the upper end of the side platebody, the first insert plate being inserted into the upper plate memberand seated onto an inner surface of the upper plate member; a secondinsert plate protruding downwards from the lower end of the side platebody such that a stepped portion is formed therebewteen, the secondinsert plate being inserted into the lower plate member and seated ontothe stepped portion formed on the corresponding bottom side panel of thelower plate member; and front and rear end parts bent from the front andrear ends of the side plate body towards the opposing other side platebody, the front and rear end parts extending in a vertical direction,wherein each of the first insert plate and the second insert plateincludes guides extending towards the front and rear end parts, and benttowards the opposing other side plate body, and protruding from thefront and rear end parts.

In an embodiment, the end plate body may include an outer plate placedupright at an outer position, and an inner plate attached to an innersurface of the outer plate at a position spaced apart from the outerplate, whereby spaces are defined between opposite side edges of theouter plates and the inner plates, thus forming insert slots into whichthe corresponding guides are inserted.

In an embodiment, each of the end plate members may further include aheat dissipation window through which heat generated by the batterymodule is dissipated.

In an embodiment, each of the battery cells may include a front caseplate and a rear case plate respectively disposed on a front surface anda rear surface of a bare cell, the bare cell being provided with batterytabs through which power is input into or output from the bare cell, thefront and rear case plates being removably coupled to each other,wherein the front case plate includes: front horizontal framesrespectively provided on upper and lower ends of the front case plate,each of the front horizontal frames extending in a horizontal directionand forming a horizontal surface; and front vertical side frames formingupright surfaces extending in a vertical direction between opposite endsof the front horizontal frames, and the rear case plate includes: rearhorizontal frames respectively provided on upper and lower ends of therear case plate, each of the rear horizontal frames extending in ahorizontal direction and forming a horizontal surface; and rear verticalside frames forming upright surfaces extending in a vertical directionbetween opposite ends of the rear horizontal frames, wherein when thefront case plate is seated into an inner surface of the rear case plate,outer surfaces of the front horizontal frames are brought into closecontact with inner surfaces of the corresponding rear horizontal frames,and outer surfaces of the front vertical side frames are brought intoclose contact with inner surfaces of the corresponding rear verticalside frames such that the front case plate is fitted into the rear caseplate.

In an embodiment, the front case plate may have at least one firstlocking depression formed in the front horizontal frame that is providedon the upper end of the front case plate, and the rear case plate mayinclude a locking member provided in the rear horizontal frame that isprovided on the upper end of the rear case plate, and the locking memberhas a hook on a lower surface thereof so that the hook of the lockingmember is locked to the first locking depression.

In an embodiment, the front case plate may further include at least onesecond locking depression formed in the front horizontal frame that isprovided on the lower end of the front case plate and extends in thehorizontal direction. The rear case plate may further include a lowerstopper protruding upwards from the horizontal surface of the rearhorizontal frame that is provided on the lower end of the rear caseplate and extends in the horizontal direction, the lower stopper beinglocked into the second locking depression.

In an embodiment, the front case plate may include: a front plate bodyhaving a planar inner surface with which the bare cell is brought intoclose contact, and an outer surface on which the front horizontal framesand the front vertical side frames are provided; a front heatdissipation window formed through the front plate body to dissipate heatgenerated by the bare cell; a front support bar provided in the frontheat dissipation window and extending in the vertical direction; andfront tab guides protruding upwards from an upper surface of the fronthorizontal frame that is provided on the upper end of the front caseplate, the front tab guides guiding the corresponding battery tabs ofthe bare cell.

In an embodiment, the rear case plate may include: a rear plate bodyhaving a planar inner surface with which the bare cell is brought intoclose contact, with the rear horizontal frames and the rear verticalside frames provided on the inner surface of the rear plate body; a rearheat dissipation window formed through the rear plate body to dissipateheat generated by the bare cell; a rear support bar provided in the rearheat dissipation window and extending in the vertical direction; andrear tab guides protruding upwards from an upper surface of the rearhorizontal frame that is provided on the upper end of the rear caseplate, the rear tab guides guiding the corresponding battery tabs of thebattery cell.

In an embodiment, the front case plate may further include a concavepart depressed in each of the front vertical side frames provided on theopposite ends of the outer surface of the front case body that is notbrought into contact with the bare cell, and the rear case plate mayfurther include a convex part protruding inwards from each of the rearvertical side frames such that the convex part corresponds to theassociated concave part of the front case plate, wherein the convex parthas a coupling hole formed in a first surface thereof oriented towardsthe front case plate, and a coupling protrusion provided on a secondsurface thereof opposite to the coupling hole.

In an embodiment, a lithium battery may include: a battery module havingbattery cells electrically connected to each other such that power ofdifferent poles is input into or output from the battery cells; an upperplate member forming an upper surface of the lithium battery, the upperplate member covering an upper end of the battery module contained inthe lithium battery; a lower plate member forming a bottom plate of aspace that contains the battery module therein; and side plate membersplaced upright, the side plate members being coupled at upper endsthereof to the upper plate member and coupled at lower ends thereof tothe lower plate member, wherein the upper plate member includes aconnection plate extending from a top surface of the upper plate memberin one direction, with a locking protrusion produced under a lowersurface of the connection plate; an open slot formed in the top surfaceat a position opposite to the connection plate, the open slot having ashape corresponding to a distal end of the connection plate; and aconnection hole formed inside the open slot so that the lockingprotrusion of the connection plate is removably locked into theconnection hole.

In an embodiment, the upper plate member may further include at leastone first locking slot formed in each of vertical extension panels thatextend from opposite side edges of the top surface, the lower platemember may further include at least one second locking slot formed ineach of side panels that vertically protrude upwards from opposite sideedges of the bottom plate, and each of the side plate members mayfurther include: a first elastic protrusion provided on an upper end ofthe side plate member, the first elastic protrusion being locked to thecorresponding first locking slot; and a second elastic protrusionprovided on a lower end of the side plate member that is inserted insidethe corresponding side panel of the lower plate member, the secondelastic protrusion being locked to the corresponding second lockingslot.

In an embodiment, each of the side plate members may include a sideplate body coupled at an upper end thereof to the upper plate member andcoupled at a lower end thereof to the lower plate member, and thebattery module may include at least one battery cell having a cell caseand bare cells provided on front and rear surfaces of the cell case suchthat the cell case and the bare cells alternate with each other, whereinone side surface of each of outermost bare cells is supported by thefront or rear surface of the cell case, and a remaining side surface ofthe outermost bare cell is supported by an inner surface of thecorresponding side plate body.

In an embodiment, each of the first and second elastic protrusions maybe configured such that a proximal end thereof extends from thecorresponding side plate member, a hook is provided on a distal endthereof, the hook being locked into a corresponding one of the first andsecond locking slots, and opposite side edges thereof are separated fromthe side plate member.

In an embodiment, each of the battery cells may include a cell casecontaining pouch type bare cells, the cell case including: a case bodyplaced upright and receiving the bare cells, the cell case having anupper horizontal frame and a lower horizontal frame respectivelyprovided on upper and lower edges of the case body, and vertical sideframes extending between opposite ends of the upper and lower horizontalframes; a coupling protrusion protruding from a first surface of thecase body in one direction; and a coupling hole formed in a secondsurface of the case body so that the coupling protrusion of another cellcase is inserted into the coupling hole.

In an embodiment, either of the side plate members may further includean insert protrusion provided on at least one surface thereof that facesthe battery module contained in the lithium battery, the insertprotrusion being inserted into the coupling hole of the cell case.

In an embodiment, the cell case may include tab guides protrudingupwards from an upper end of the case body, wherein the tab guidesincludes: a pair of tab guides disposed at a side corresponding to thefront surface of the case body at positions spaced apart from eachother; and a pair of tab guides disposed at a side corresponding to therear surface of the case body at positions spaced apart from each other.

In an embodiment, the cell case may further include a circuit boardsupport protrusion protruding upwards from the upper horizontal framethat forms an upper surface of the case body, the circuit board supportprotrusion supporting a circuit board, wherein the circuit board supportprotrusion includes two rods spaced apart from each other, with a hookprotruding from an upper end of each of the two rods, the hook having adownwardly inclined surface.

In an embodiment, the cell case may further include: a heat dissipationwindow formed in the case body to dissipate heat generated by the barecells; horizontal support frames provided in the case body and formingplanar surfaces extending in the horizontal direction on upper and loweredges of the heat dissipation window so that the bare cells arerespectively seated onto the front and rear surfaces of the case body;and a support bar vertically provided in a medial portion of the heatdissipation window and fastened to the horizontal support frames.

In an embodiment, the cell case may further include: a plurality ofvertical partition ribs provided on the front and rear surfaces of thecase body, each of the vertical partition ribs extending a predeterminedlength vertically; and a plurality of horizontal partition ribs providedon the front and rear surfaces of the case body, each of the horizontalpartition ribs extending a predetermined length horizontally.

In an embodiment, each of the side plate members may further include aplurality of heat dissipation slots formed in the side plate member todissipate heat generated by the battery module.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentinvention will be more clearly understood from the following detaileddescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a perspective view showing a lithium battery, according to anembodiment of the present invention;

FIG. 2 is an exploded perspective view showing the lithium batteryaccording to the embodiment of the present invention;

FIG. 3 is a plan view showing side plate members of the lithium batteryaccording to the embodiment of the present invention;

FIG. 4 is a plan view showing an end plate member of the lithium batteryaccording to the embodiment of the present invention;

FIG. 5 is a plan view illustrating the coupling relationship between theend plate members and the side plate members of the lithium batteryaccording to the embodiment of the present invention;

FIG. 6 is a perspective view illustrating the connection of severallithium batteries according to the embodiment of the present invention;

FIG. 7 is a plan view illustrating the connection of the lithiumbatteries according to the embodiment of the present invention;

FIG. 8 is an exploded perspective view of a battery cell of the lithiumbattery according to the embodiment of the present invention;

FIG. 9 is a perspective view of the battery cell of the lithium batteryaccording to the embodiment of the present invention;

FIG. 10 is a perspective view showing a locking member of the lithiumbattery according to the embodiment of the present invention;

FIG. 11 is a side sectional view of the locking member of the lithiumbattery according to the embodiment of the present invention;

FIG. 12 is a perspective view illustrating a lithium battery, accordingto another embodiment of the present invention;

FIG. 13 is a plan view showing the lithium battery of FIG. 12;

FIG. 14 is an exploded perspective view showing the lithium battery ofFIG. 12;

FIG. 15 is a front perspective view of a cell case of the lithiumbattery according to an embodiment of the present invention;

FIG. 16 is an exploded perspective view showing the battery cell of thelithium battery according to an embodiment of the present invention;

FIG. 17 is a rear perspective view of the cell case of the lithiumbattery according to an embodiment of the present invention; and

FIG. 18 is a perspective view illustrating a process of connectingseveral lithium batteries of FIG. 12 to each other according to anembodiment of the present invention;

DETAILED DESCRIPTION

Hereinafter, embodiments of a lithium battery according to the presentinvention will be described in detail with reference to the attacheddrawings.

FIG. 1 is a perspective view showing the lithium battery according to anembodiment of the present invention. FIG. 2 is an exploded perspectiveview showing the lithium battery.

Referring to FIGS. 1 and 2, the lithium battery according to anembodiment of the present invention includes a battery module whichincludes one or more battery cells connected to each other, side platemembers 120 which are disposed on opposite sides of the battery module,an upper plate member 110 which is provided on upper ends of the sideplate member 120, a lower plate member 130 which forms the bottom of aspace that contains the battery cells, and end plate members 140 whichare provided on front and rear ends of the side plate members 120 thatare spaced apart from each other.

The battery module includes the battery cells that are electricallyconnected to each other. The battery module is placed on the lower platemember 130. Each battery cell includes a pouch type bare cell (220, seeFIGS. 8 and 9), a front case plate (240, see FIGS. 8 and 9) and a rearcase plate (230, see FIGS. 8 and 9). The bare cell 220 includes a cellbody 222 which outputs power or is charged with power, and battery tabs221 through which power is input into or output from the cell body 222.The front and rear case plates 240 and 230 are disposed on front andrear surfaces of the bare cell 220 and are separably coupled to eachother.

Several battery cells each of which has the above-mentioned constructionare electrically connected to each other, forming a single batterymodule. The battery module is housed in a case of the lithium battery.The construction and operation of the battery cell will be explainedlater with reference to FIGS. 8 through 11.

The upper plate member 110 includes a top surface 114, a verticalextension panel 115, upper depressions 115 a and upper locking slots112. The top surface 114 has electrode pole holes 111 through whichelectrode poles protrude outwards from the top surface 114. The verticalextension panel 115 extends downwards from front, rear, left and rightedges of the top surface 114, thus forming front, rear, left and rightsurfaces of the upper plate member 110. The upper depressions 115 a aredepressed inwards from the vertical extension panel 115, thus formingstepped portions. The upper locking slots 112 are respectively formed inthe opposite end surfaces of the vertical extension panel 115.

The vertical extension panel 115 includes surfaces that extend downwardsfrom the edges of the top surface 114, and the opposite side surfaces ofthe vertical extension panel 115 are curved in the sideways direction.The vertical extension panel 115 has upper depressions 115 a formed inthe respective opposite side surfaces. In an embodiment, the shape andsize of each upper depression 115 a correspond to those of a connectiondepression 122 of the corresponding side plate member 120 which will beexplained later.

Further, the vertical extension panel 115 has upper stepped portions,formed in the lower edge thereof, each of which has a shapecorresponding to a lower stepped portion 132 a that is formed in each ofinner side surfaces of the lower plate member 130, as shown in FIG. 2.However, one difference is that the stepped portions (not shown) thatare formed in the inner side surfaces the vertical extension panel 115are depressed upwards unlike the lower stepped portions 132 a that aredepressed downwards in the inner side surfaces of the lower plate member130. This will be able to be easily understood by those skilled in thisart. Upper ends of the side plate members 120 are inserted and seatedonto the corresponding stepped portions of the vertical extension panel115.

The upper locking slots 112 are respectively formed through the oppositeend surfaces of the vertical extension panel 115 of the upper platemember 110. The end plate members 140 are locked to the correspondingupper locking slots 112.

The side plate members 120 will be explained with reference to FIG. 3.

FIG. 3 is a plan view illustrating the side plate members 120 of thelithium battery according to an embodiment of the present invention.

Referring to FIG. 3, the side plate members 120 are located at positionswhere they are spaced apart from each other by a predetermined distance.Each side plate member 120 includes a side plate body 121 which isplaced upright; an upper insert plate 123 which is inserted into thevertical extension panel 115; a lower insert plate 126 which is providedon the lower edge of the side plate body 121 and is inserted into thelower plate member 130; and front and rear end parts 125 which arerespectively bent from the front and rear edges of the side plate body121 and extend in the vertical direction. A connection depression 122 isformed downwards in the upper end of the side plate body 121 of one ofthe side plate members 120. A connection plate 124 is provided on theside plate body 121 of the other side plate member 120 so that theconnection plate 124 can be coupled to the connection depression 122 ofanother lithium battery.

The two main side plate bodies 121 are provided at positions spacedapart from each other and are placed upright at opposite sides on thelower plate member 130.

The upper insert plate 123 protrudes upwards from the upper edge of theside plate body 121 and is seated into the corresponding one of thestepped portions each of which is formed in the inner surface of thelower end of the vertical extension panel 115. The opposite ends of theupper insert plate 123 are bent towards the other side plate body 121,thus forming a guide 123 a for the connection with the end plate members140.

The lower insert plate 126 protrudes downwards from the lower edge ofthe side plate body 121 and is seated into the corresponding one of thelower stepped portions 132 a that are formed in the inner surface of theupper end of the lower plate member 130.

The front and rear end parts 125 are perpendicularly bent from the frontand rear edges of the side plate body 121 towards the central portion ofthe lithium battery. Each of the front and rear end parts 125 extends inthe vertical direction. The upper insert plate 123 extends upwards fromthe upper edges of the front and rear end parts 125 in a shape in whichthe guide 123 a protrudes upwards inside the front and rear end parts125.

The connection depression 122 is a depression which is formed in astepped shape in the upper end of one of the main side plate bodies 121and 121′, for example, of the side plate body 121. A partition 122 athat extends in the vertical direction is provided in the connectiondepression 122 so that the space in the connection depression 122 ispartitioned into two or more spaces.

The connection plate 124 extends outwards from the other of the mainside plate bodies 121 and 121′, for example, the side plate body 121′that does not have the connection depression 122, so that connectionplate 124 can be removably coupled to the connection depression 122 ofthe side plate body 121 of an adjacent lithium battery. To achieve this,a connection protrusion 124 a which is locked into the connectiondepression 122 may be provided under the lower surface of the connectionplate 124.

The connection protrusion (124 a, refer to FIGS. 3 and 7) is aprotrusion that protrudes downwards from the lower surface of theconnection plate 124. The number of connection protrusions may be thesame as that of the connection depression 122 or there be provided asmany as needed to maintain the connection between the adjacent lithiumbatteries.

The end plate members 140 are respectively inserted into front and rearends of the two main side plate bodies 121, thus closing the front andrear surfaces of the lithium battery. The end plate member 140 isillustrated in FIGS. 2 and 4. FIG. 4 is a plan view showing the endplate member 140.

Referring to FIG. 4, each end plate member 140 includes an end platebody 141, an upper fastening part 143, a lower fastening part 146, aheat dissipation window 142, 142′ and insert slots 144. The end platebody 141 includes an outer plate 141 a which is placed upright, and aninner plate 141 b which is disposed at a predetermined position spacedapart from an inner surface of the outer plate 141 a. The upperfastening part 143, 143′ is provided on an upper end of the end platebody 141 so that the end plate body 141 is fastened to the upper platemember 110 by the upper fastening part 143, 143′. The lower fasteningpart 146 is provided under a lower end of the end plate body 141 so thatthe end plate body 141 is fastened to the lower plate member 130 by thelower fastening part 146. The heat dissipation window 142, 142′ isformed through the outer plate 141 a and the inner plate 141 b todissipate heat generated inside the lithium battery. The insert slots144 are formed by spaces defined between the outer plate 141 a and theinner plate 141 b.

The end plate bodies 141 of the end plate members 140 are respectivelyinserted into the front and rear end parts 125 of the side plate bodies121, thus closing off the front and rear ends of the side plate members120. The upper and lower ends of the end plate body 141 are coupled tothe upper plate member 110 and the lower plate member 130. Each endplate body 141 includes the outer plate 141 a and the inner plate 141 b.

The outer plate 141 a and the inner plate 141 b are upright plates whichare bonded to each other such that a space is formed between theirupper, lower and opposite side ends. The outer plate 141 a is disposedat an outer position, while the inner plate 141 b is disposed at aninner position and seated onto the stepped portion formed in thecorresponding one of the front and rear end parts 125 of the side platebodies 121.

The insert slots 144 are formed by spaces defined between the oppositeside edges of the outer plate 141 a and the inner plate 141 b. The guide123 a of the side plate bodies 121 and 121′ is inserted into the insertslots 144 in such a way that the end plate member 140 is moved downwardsalong the corresponding ends of the front and rear end parts 125 of theside plate bodies 121 and 121′ to fasten the end plate member 140 to theside plate bodies 121 and 121′.

The structure that couples the guide 123 a to the insert slot 144 isclearly shown in the partially enlarged view of FIG. 5. The guide 123 aextends from the upper insert plate 123 and the lower insert plate 126of the side plate body 121, and the opposite ends thereof are benttowards the opposing side plate body.

The guide 123 a is inserted into the corresponding insert slot 144between the outer plate 141 a and the inner plate 141 b and guides theend plate member 140 so that the end plate member 140 can slide in thevertical direction. This allows the end plate member 140 to be coupledto the side plate bodies 121.

As such, the shape of the guide 123 a is such that the front end thereofis bent from each of the opposite ends of each side plate boby andprotrudes a predetermined distance so that it can be inserted into thecorresponding insert slot 144. Furthermore, a stepped portion 123 b, 123b′ is formed adjacent to the front end of the guide 123 a, so that thecorresponding side edge of the inner plate 141 b is seated onto thestepped portion 123 b, 123 b′.

The upper fastening part 143, 143′ includes at least one first insertprotrusion 143 b, 143 b′ which protrudes upwards from the upper end ofthe end plate body 141, and a first locking protrusion 143 a, 143 a′which is locked to the corresponding upper locking slot 112 of the upperplate member 110.

The first insert protrusion 143 b, 143 b′ protrudes upwards from theupper end of each end plate body 141. In this embodiment, the firstinsert protrusion 143 b, 143 b′ is an upright plate and is seated ontothe stepped portion formed in the inner surface of the verticalextension panel 115 of the upper plate member 110.

The first locking protrusion 143 a, 143 a′ is an upright plate which isprovided with a hook formed on the end thereof. The first lockingprotrusion 143 a, 143 a′ is inserted into the upper plate member 110 andis locked to the upper locking slot 112 using the hook.

The lower fastening part 146 includes at least one second insertprotrusion 146 b which protrudes downwards from the lower end of the endplate body 141, and a second locking protrusion 146 a which is locked toa corresponding lower locking slot 134 of the lower plate member 130.

The second insert protrusion 146 b protrudes downwards from the lowerend of each end plate body 141. In this embodiment, the second insertprotrusion 146 b is a plate which extends downwards and is seated ontothe stepped portion formed in the inner surface of the lower platemember 130.

The heat dissipation window 142, 142′ is formed in each end plate body141, and a plurality of connection bars 142 a are horizontally providedin the heat dissipation window 142, 142′ to discharge internal heat tothe outside and prevent foreign substances from entering the lithiumbattery. To achieve this, the connection bars 142 a may be horizontallyoriented and fixed in the heat dissipation window 142, 142′ atpredetermined angles such that their upper surfaces are inclineddownwards with respect to the outward direction.

The lower plate member 130 includes a bottom plate 131 which supportsthe battery module thereon; bottom end panels 133 and bottom side panels132 which are provided upright on opposite ends and opposite side edgesof the bottom plate 133; lower locking slots 134 which are formed in therespective bottom end panels 133 and to which the corresponding secondlocking protrusions 146 a are removably locked; and lower steppedportions 132 a which are provided on the inner surfaces of the bottomend panels 133 and the bottom side panels 132 so that the lower ends ofthe end plate members 140 and the lower ends of the side plate members120 are inserted into the lower plate member 130 and seated onto thelower stepped portions 132 a.

The bottom plate 131 is a planar plate which provides a space in whichto contain the at least one battery cell.

The bottom end panels 133 extend upwards from the front and rear ends ofthe bottom plate 131. The lower ends of the end plate bodies 141,particularly, the second insert protrusions 146 b and 146 b′, areinserted inside the bottom end panels 133 and are brought into closecontact with the corresponding bottom end panels 133.

The lower locking slots 134 are formed in the respective bottom endpanels 133. The hooks of the second locking protrusions 146 a and 146 a′that are inserted into the lower plate member 130 are inserted andlocked into the corresponding lower locking slots 134.

The bottom side panels 132 vertically protrude upwards from the oppositeside edges of the bottom plate 131. The lower ends of the side platebodies 121 are inserted into the lower plate member 130 and are broughtinto close contact with the inner surfaces of the bottom side panels132. In an embodiment of the present invention, the shape of each bottomside panel 132 corresponds to that of the corresponding upper depression115 a of the upper plate member 110. The lower stepped portions 132 aare formed on the inner surfaces of the bottom side panels 132 such thatthe second insert protrusions 146 b of the end plate members 140 and thelower insert plates 126 of the side plate members 120 are seated ontothe corresponding lower stepped portions 132 a. Here, the lower steppedportions 132 a may be formed on the inner surfaces both of the bottomend panels 133 and of the bottom side panels 132.

FIGS. 6 and 7 are, respectively, a perspective view and a plan viewillustrating the connection of several lithium batteries having theabove-mentioned construction.

First, the assembly of each lithium battery will be explained.

Referring to FIGS. 6 and 7, the second insert plates 126 that protrudefrom the lower ends of the side plate bodies 121 are inserted into thelower plate member 130 such that they are brought into close contactwith the inner surfaces of the bottom side panels 132 and are seatedonto the lower stepped portions of the lower plate member 130.Thereafter, the end plates bodies 141 and 141′ are respectively insertedinto the front and rear ends of the open space between the side platebodies 121.

In detail, the end plate bodies 141 and 141′ are located above thecorresponding guide 123 a of the front and rear end parts 125 of theside plate bodies 121 such that the insert slots 144 of the end platebodies 141 and 141′ are aligned with the corresponding guide 123 a.Subsequently, the end plate bodies 141 and 141′ are moved downwards sothat the guide 123 a is inserted into the corresponding insert slots 144of the end plate bodies 141 and 141′.

In this process, the end plate bodies 141 and 141′ are moved downwardsuntil the second insert protrusions 146 b of the lower fastening part146 formed on the lower ends of the end plate bodies 141 and 141′ reachthe lower stepped portions 132 a formed on the inner surfaces of thebottom end panels 133. The second locking protrusions 146 a and 146 a′are locked to the corresponding second locking slots 134 that are formedin the bottom end panels 133 of the lower plate member 130. As a result,the end plate members 140, the side plate members 120 and the lowerplate member 130 can be reliably fastened to each other.

Subsequently, the battery module that includes several battery cellsconnected to each other is placed onto the bottom plate 131 of the lowerplate member 130. The upper plate member 110 is coupled to the sideplate members 120 and the end plate members 140, thus closing off theinternal space that contains the battery module.

At this time, the upper insert plates 123 of the side plate members 120are seated onto the stepped portions that are formed in the lower end ofthe vertical extension panel 115. Further, the first locking protrusions143 a and 143 a′ of the upper fastening part 143 and 143′ provided onthe end plate members 140 are locked to the corresponding upper lockingslots 112. The first insert protrusions 143 b and 143 b′ are broughtinto close contact with the inner surface of the vertical extensionpanel 115.

The lithium battery that has been assembled by the above process can beconnected to one or more other lithium batteries.

In detail, the connection plate 124 that extends in one direction fromthe side plate body 121 of a first lithium battery 100 is seated intothe connection depression 122 of a second lithium battery 100′. Indetail, the connection protrusion 124 a that protrudes downwards fromthe lower surface of the connection plate 124 is inserted into theconnection depression 122 of the second lithium battery 100′. Thereby,the first lithium battery 100 is mechanically connected to the secondlithium battery 100′.

In the same manner, a third lithium battery 100″ can also be connectedto the second lithium battery 100′. That is, the second lithium battery100′ and the third lithium battery 100″ are connected to each other insuch a way that the connection plate 124′ of the second lithium battery100′ is seated into the connection depression 122″ of the third lithiumbattery 100″ such that the connection protrusion 124 a′ is inserted intothe connection depression 122″.

In the lithium battery according to an embodiment of the presentinvention, the number of battery cells that are contained in the singlelithium battery can be determined depending on a desired level of outputpower. For instance, when a battery of 50 A is required, a batterymodule including two 25 A bare cells can be used. If a battery of 100 Ais needed, a battery module including four 25 A bare cells can be used.

If the number of bare cells increases, the entire size of the singlelithium battery must also be increased. However, for convenience, thelithium battery may be designed in a comparatively small size.

Therefore, in the embodiments of the present invention, to reduce thesize of the battery, front and rear case plates 240 and 230 that containeach bare cell 220 have asymmetrical structures to reduce the thicknessof a single cell unit that is formed by the coupling of the front andrear case plates 240 and 230 with the single bare cell 220 interposedtherebetween.

The battery cell module including at least one battery cell will beexplained with reference to FIGS. 8 through 11.

FIG. 8 is an exploded perspective view of a battery cell of the lithiumbattery according to an embodiment of the present invention. FIG. 9 is aperspective view of the battery cell of the lithium battery according toan embodiment of the present invention.

Referring to FIGS. 8 and 9, the battery module includes at least onebattery cell. The battery cell includes a bare cell 220, and the frontand rear case plates 240 and 230 which are coupled to each other withthe bare cell 220 interposed therebetween.

The bare cell 220 includes a cell body 222 and a pair of battery tabs221 which protrude upwards from the cell body 222 at positions spacedapart from each other and output different powers. The cell body 222 hasupper, lower, left and right frame parts with which the front and rearcase plates 240 and 230 are brought into close contact.

The front case plate 240 and the rear case plate 230 have structuresthat are to asymmetrical. The bare cell 220 is disposed between thefront case plate 240 and the rear case plate 230, and the front caseplate 240 is seated into an inner surface 231 a of the rear case plate230.

In detail, the front case plate 240 includes a front plate body 241, afront heat dissipation window 242, a front support bar 243, a front tabguide 245, front horizontal frames 242 a, front vertical side frames 242b, first locking depressions 244 and second locking depressions 246. Thefront plate body 241 has an inner surface and an outer surface 241 b andis placed upright. The first heat dissipation window 242 is formed inthe front plate body 241 to dissipate heat generated by the bare cell220. The first support bar 243 is provided upright in the first heatdissipation window 242 and is brought into contact with the frontsurface of the bare cell 220 to support it. The front tab guides 245protrude upwards from the upper end of the front plate body 241 andsupport the corresponding battery tabs 221 of the bare cell 220. Thefront horizontal frames 242 a horizontally extends along upper and loweredges of the front plate body 240 and protrude in a direction away fromthe bare cell 220 to form horizontal plates. The front vertical sideframes 242 b vertically extend from the opposite ends of the fronthorizontal frames 242 a. The first locking depressions 244 and thesecond locking depressions 246 are respectively formed in the upper andlower front horizontal frames 242 a.

The inner surface 241 b of the front plate body 241 is a surface that isplaced upright and is brought into close contact with the bare cell 220.The front horizontal frames 242 a and the front vertical side frames 242b protrude from the upper, lower, left and right edges of the outersurface 241 a.

The front horizontal frames 242 a are horizontal surfaces that areprovided on the upper and lower edges of the front plate body 241 andprotrude in the direction away from the bare cell 220. When the frontcase plate 240 is coupled to the rear case plate 230 with the bare cell220 disposed therebetween, the front horizontal frames 242 a are seatedonto the inner surface 231 a of the rear case plate 230 and are broughtinto close contact with inner surfaces of rear horizontal frames 232 awhich will be explained later, so that the front case plate 240 isfitted into the rear case plate 230.

The front vertical side frames 242 b are vertical surfaces which areprovided on the opposite ends of the front plate body 241. The frontvertical side frames 242 b protrude in the direction away from the barecell 10. Each front vertical side frame 242 b includes a concave part248 which corresponds to a convex part 238 that protrudes from thecorresponding rear vertical side frame 232 b towards the central portionof the battery.

The concave part 248 is a curved part that is depressed inwards from theouter surface of the front vertical side frame 242 b and protrudesforwards from the front vertical side frame 242 b.

The first locking depressions 244 are formed by cutting off portions ofthe front horizontal frame 242 a that is provided on the upper end ofthe front plate body 241. The second locking depressions 246 are formedby cutting off portions of the front horizontal frame 242 a that isprovided on the lower end of the front plate body 241. Locking members234 and lower stoppers 236 of the rear case plate 230 which will beexplained later are locked into the corresponding first lockingdepressions 244 and the corresponding second locking depressions 246 sothat the front case plate 240 that is seated onto the inner surface 231a of the rear case plate 230 is fastened to the rear case plate 230.

The front heat dissipation window 242 is an opening which is formed in acentral portion of the front case plate 240 to dissipate heat generatedby the bare cell 220.

The front case plate 240 further includes a front partition 247 which isprovided around the front heat dissipation window 242 and protrudes fromthe outer surface 241 a of the front case plate 240.

Protrusions 249 are provided on the front partition 247 at positionscorresponding to the associated concave parts 248. Each protrusion 249protrudes from the corresponding one of the opposite side parts of thefront partition 247 to a distance corresponding to the length to whichthe concave part 248 protrudes from the front case plate 240.

The front support bar 243 is vertically provided between upper and lowerends of the front heat dissipation window 242 and supports the bare cell220 disposed between the front case plate 240 and the rear case plate230. The front support bar 243 is provided between planar surfaces thatform the upper and lower ends of the front heat dissipation window 242.In detail, the front support bar 243 is provided on the upper surface ofthe front partition 247 that horizontally extends along the lower end ofthe front heat dissipation window 242, and the front heat dissipationwindow 242 is disposed on an edge of the upper surface of the frontpartition 247 that is on the side away from the bare cell 220. Thereby,a space is defined between the bare cell 220 and the front support bar243.

The front tab guides 245 protrude from the front plate body 241 upwardsand guide the battery tabs 221 of the bare cell 220. In this embodiment,each front tab guide 245 is a vertical plate which protrudes upwardsfrom the upper surface of the front horizontal frame 242 a.

The rear case plate 230 includes a rear plate body 231, a rear heatdissipation window 232, a rear support bar 233, the convex parts 238,circuit board support protrusions 214, rear tab guides 235, rearhorizontal frames 232 a, rear vertical side frames 232 b, lockingmembers 234, a rear partition 237 and coupling protrusions 239. The rearplate body 231 is placed upright and includes the inner surface 231 a onwhich the bare cell 210 is supported, and an outer surface 231 b towhich the front case plate of another bare cell is coupled. The secondheat dissipation window 232 is an opening that is formed in the rearplate body 231. The rear support bar 233 is vertically provided in thesecond heat dissipation window 232 to support the bare cell 220. Theconvex parts 238 protrudes inwards from the rear vertical side frames232 b and are seated into the corresponding concave part 248 of thefront case plate 240. The circuit board support protrusions 214 supporta circuit board (not shown) which is placed on the upper end of thebattery cell. The rear tab guides 235 guide the corresponding batterytabs 221. The rear horizontal frames 232 a horizontally extend alongupper and lower edges of the rear plate body 231 and protrude in adirection toward the bare cell 220 to form horizontal plates. The rearvertical side frames 232 b vertically extend from the opposite ends ofthe upper rear horizontal frame 232 a to the lower rear horizontal frame232 a. The locking members 234 are locked into the corresponding firstlocking depressions 244 of the front case plate 240. The rear partition237 is provided around the rear heat dissipation window 232 of the rearplate body 231 and protrudes from the rear plate body 231 in a directionaway from the bare cell 210. The coupling protrusions 239 protrude fromthe opposite ends of the outer surface of the rear plate body 231

The rear horizontal frames 232 a are horizontal surfaces that areprovided on the upper and lower edges of the rear case plate 230 andprotrude from the rear case plate 230 forwards and rearwards. When thefront case plate 240 is seated onto the inner surface 231 a of the rearcase plate 230, the front horizontal frames 242 a are brought into closecontact with the inner surfaces of the rear horizontal frames 232 a sothat the front case plate 240 is fitted into the rear case plate 230.

The rear vertical side frames 232 b vertically extend from the oppositeends of the rear horizontal frames 232 a so that the upper and lowerrear horizontal frames 232 a are connected to each other.

The convex parts 238 protrude from the medial portions of the rearvertical side frames 232 b towards the second heat dissipation window232. Thus, when the front case plate 240 is seated into the innersurface 231 a of the rear case plate 230, the convex parts 238 areinserted into the corresponding concave parts 248 so that the front caseplate 240 can be reliably fastened to the rear case plate 230.

A coupling hole 238 a is formed in a surface of each convex part 238that faces the front case plate 240. The coupling protrusions 239 areprovided on the outer surface of the rear case plate 230 at positionscorresponding to the coupling holes 238 a.

The coupling holes 238 a are coupled to the corresponding couplingprotrusions 239 that are provided on an adjacent battery cell.

That is, the coupling hole 238 a is formed in the surface of the convexpart 238 that corresponds to the inner surface 231 a of the rear caseplate 230 that faces the front case plate 240. The coupling protrusion239 that has a bar shape is provided on the outer surface 231 b of tothe rear case plate 230 that is opposite to the surface of the convexpart 238 that has the coupling hole 238 a.

The rear partition 237 is provided on the upper, lower, left and rightends of the rear heat dissipation window 232 and protrudes from theouter surface of the rear plate body 231 in the direction away from thebare cell 220.

The rear heat dissipation window 232 is an opening that is formed in therear plate body 231 to dissipate heat generated by the bare cell 220.

The rear support bar 233 vertically extends a predetermined length andconnects the upper and lower ends of the rear partition 237 to eachother. The function of the rear support bar 233 is to support the barecell 220.

Each locking member 234 will be described in detail with reference toFIGS. 10 and 11.

FIG. 10 is an enlarged perspective view of the locking member accordingto an embodiment of the present invention. FIG. 11 is a side sectionalview of FIG. 10.

Referring to FIGS. 10 and 11, the locking member 234 includes a verticalpart 234 b which extends from the rear plate body 231, a horizontal part234 a which is bent from the vertical part 234 b, and a hook 234 c whichprotrudes downwards from the inner surface of the horizontal part 234 a.

The vertical part 234 b is configured such that a proximal end thereofextends from the rear plate body 231 and opposite side edges thereof areseparated from the rear plate body 231. Therefore, the vertical part 234b can elastically move upwards or downwards on its proximal end that isfixed to the rear plate body 231.

The horizontal part 234 a is bent from an upper end of the vertical part234 b. The horizontal part 234 a is separated from the rear horizontalframe 232 a.

The hook 234 c protrudes downwards from the inner surface of thehorizontal part 234 a. The hook 234 c has an inclined surface whichextends from the end of the horizontal part 234 a at a predeterminedangle, and a vertical surface which is bent from a lower end of theinclined surface in the vertical direction.

As shown in FIG. 11, the locking member 234 is inserted into thecorresponding first locking depression 244 of the front horizontal frame242 a of the front case plate 240, and the hook 234 c is locked to astop portion of the first locking depression 244 of the front case plate240, thus fastening the front case plate 240 to the rear case plate 230.

The rear plate body 231 further includes lower stoppers 236 whichprotrude upwards from the surface of the rear horizontal frame 232 a andare seated into the corresponding second locking depression 246 that areformed in the front horizontal frame 242 a. In this embodiment, thelower stoppers 236 are disposed on the rear horizontal frame 232 a atpositions spaced apart from each other.

Each circuit board support protrusion 251 includes a support rod 251 bwhich protrudes upwards from the upper end of the rear plate body 231. Atriangular hook 251 a that has a downwardly inclined surface is providedon the upper end of the support rod 251 b.

Each rear tab guide 235 has a depression which is formed by cutting offa portion of the rear horizontal frame 232 a that horizontally extendsfrom the upper end of the rear plate body 231, thus forming a space intowhich the corresponding front tab guide 245 is inserted. The rear tabguide 235 protrudes upwards from a portion of the rear horizontal frame232 a that surrounds the depression. The rear tab guide 235 is coupledto the corresponding front tab guide 245, thus guiding and supportingthe corresponding battery tab 221 of the bare cell 220 so that thebattery tab 221 protrudes upwards from the front and rear tab guides 245and 235.

The battery cell according to an embodiment of the present invention hasthe above-mentioned construction, and the assembly and effect thereofwill be explained below.

First, the bare cell 220 is located on the inner surface of the rearcase plate 230. The cell body 222 of the bare cell 220 is brought intoclose contact with the rear heat dissipation window 232, and the batterytabs 221 are seated into the rear tab guides 235.

Thereafter, the front case plate 240 is inserted inside the rearhorizontal frames 232 a and the rear vertical side frames 232 b of therear case plate 230, and the inner surface of the front to case plate240 is brought into close contact with the bare cell 220 and the innersurface 231 a of the rear case plate 230.

That is, the front horizontal frames 242 a of the front case plate 240are brought into close contact with the inner surfaces of the rearhorizontal frames 232 a. The front vertical side frames 242 b of thefront case plate 240 are brought into close contact with the innersurfaces of the rear vertical side frames 232 b. At this time, theconvex parts 238 are seated into the corresponding concave parts 248.

Furthermore, the locking members 234 are locked into the correspondingfirst locking depressions 244 of the front horizontal frame 242 a whilethe front case plate 240 is fitted into the space between the rearhorizontal frames 232 a and the rear vertical side frames 232 b of therear case plate 230. In the process in which each locking member 234 islocked into the corresponding first locking depression 244, thehorizontal part 234 a of the locking member 234 can be elastically movedvertically while passing over the front horizontal frame 242 a, becausethe vertical part 234 b extends from the rear plate body 231 so as to bemovable.

Therefore, each locking member 234 can be smoothly and elasticallyhooked to the corresponding first locking depression 244.

In addition, the lower stoppers 236 that protrude from the lower rearhorizontal frame 232 a are locked into the corresponding second lockingdepressions 246. As a result, the front case plate 240 is fixed in therear case plate 230 by the locking members 234 and the lower stoppers236.

As stated above, in the present invention, the front case plate 240 canbe fixed to the rear case plate 230 in such a way that the front caseplate 240 is fitted into the rear case plate 230 that has the concavestructure. Thus, the assembly process is simplified, thereby markedlyreducing the working time.

Moreover, a process of disassembling the front and rear case plates 240and 230 from each other can also be simple. When the worker pushes theends of the horizontal parts 234 a of the locking members 234 upwards,the hook 234 c provided on the lower surfaces of the locking members 234are removed from the first locking depressions 244 of the front caseplate 240. Then, the front case plate 240 can be easily separated fromthe inner surface 231 a of the rear case plate 230.

Several battery cells each of which is assembled by the above-mentionedprocess are successively coupled to each other in such a way that thecoupling protrusion 239 of the rear case plate 230 of each battery cellis inserted into the coupling hole 238 a that is formed in the outersurface of the rear case plate 240 of an adjacent battery cell.

Hereinafter, a lithium battery according to another embodiment of thepresent invention will be described in detail with reference to theattached drawings.

FIG. 12 is a perspective view illustrating the lithium battery accordingto this embodiment of the present invention. FIG. 13 is a plan viewshowing the lithium battery of FIG. 12. FIG. 14 is an explodedperspective view showing the lithium battery of FIG. 12.

Referring to FIGS. 12 through 14, the lithium battery according to thisembodiment of the present invention includes a battery module 2000 whichincludes one or more battery cells connected to each other, side platemembers 1120 which are disposed on opposite sides of the battery module2000, an upper plate member 1110 which is provided on upper ends of theside plate member 1120, and a lower plate member 1130 which forms thebottom of a space that contains the battery cells.

The upper plate member 1110 includes a top surface 1114, a verticalextension panel 1115 and a connection plate 1113. The vertical extensionpanel 1115 extends downwards from front, rear, left and right edges ofthe top surface 1114, thus forming front, rear, left and right surfacesof the upper plate member 1110. The connection plate 1113 extends fromthe top surface 1114 in one direction. An open slot 1112 is formed in aproximal end of the connection plate 1113 to expose the top surface 1114to the outside, and the shape of the open slot 1112 corresponds to thatof a distal end of the connection plate 1113. A connection hole 1112 ais formed in the top surface 1114 inside the open slot 1112. At leastone first locking slot 1115 a is formed in each of surfaces of thevertical extension panel 1115 that face adjacent lithium batteries. Thetop surface 1114 has electrode pole holes 1111 through which electrodepoles protrude outwards from the top surface 1114.

The vertical extension panel 1115 includes surfaces that extenddownwards from the edges of the top surface 1114. The upper ends of theside plate members 1120 are inserted into and coupled to the verticalextension panel 1115.

The connection plate 1113 is a planar panel which extends from one edgeof the top surface 1114 and is bent towards the opposite edge. A lockingprotrusion 1113 a is provided under the lower surface of the end of theconnection plate 1113. The locking protrusion 1113 a is inserted intothe connection hole 1112 a formed in the top surface 1114 of an adjacentbattery case.

In detail, the locking protrusion 1113 a protrudes downwards from thelower surface of the connection plate 1113 and is inserted into theconnection hole 1112 a that is formed in the top surface 1114 of theadjacent battery case, thus connecting the lithium battery to theadjacent lithium battery. The shape of the distal end of the connectionplate 1113 corresponds to that of the open slot 1112 so that when thelithium battery is connected to the adjacent lithium battery, the distalend of the connection plate 1113 is seated into the open slot 1112 ofthe adjacent lithium battery.

The open slot 1112 is formed in the proximal end of the connection plate1113 so that the portion of the top surface 1114 that has the connectionhole 1112 a is exposed to the outside through the open slot 1112. Theshape of the open slot 1112 corresponds to that of the distal end of theconnection plate 1113. When the battery case 1100 a is connected toadjacent battery case 1100 b, the open slot of the battery case 1100 breceives the distal end of a connection plate 1113 of the battery case1100 a.

The connection hole 1112 a is formed in the portion of the top surface1114 that is exposed to the outside by the open slot 1112. The lockingprotrusion 1113 a of the connection plate 1113 of the adjacent lithiumbattery is inserted into the connection hole 1112 a. In the singlelithium battery, the connection hole 1112 a is disposed at a positionopposite to the locking protrusion 1113 a of the connection plate 1113.

The at least one first locking slot 1115 a is formed in each of thesurfaces of the vertical extension panel 1115 that face the adjacentlithium batteries. The side plate members 1120 which will be explainedlater herein are locked to the corresponding first locking slots 1115 a.

The lower ends of the side plate members 1120 are seated into the lowerplate member 1130, and the upper ends of the side plate members 1120 areinserted into the upper plate member 1110 and are brought into closecontact with the inner surface of the vertical extension panel 1115. Toachieve this, each side plate member 1120 may include a side plate body1121 which is placed upright; an upper end portion 1123 which is broughtinto close contact with the inner surface of the vertical extensionpanel 1115; at least one first elastic protrusion 1123 a which iselastically provided in the upper end portion 1123 and is locked to thecorresponding first locking slot 1115 a of the vertical extension panel1115; a lower end portion 1122 which is provided on the lower end of theside plate body 1121 and is inserted into the lower plate member 1130;at least one second elastic protrusion 1122 a which is elasticallyprovided in the lower end portion 1122 and is locked to the lower platemember 1130; and a heat dissipation slot 1124 which is formed in theside plate body 1121 to dissipate heat to the outside.

The two side plate bodies 1121 and 1121′ are provided at positionsspaced apart from each other and are placed upright at opposite sides onthe lower plate member 1130. The upper ends of the side plate bodies1121 and 1121′ are inserted into the upper plate member 1110.

The upper end portion 1123 is provided on the upper end of the sideplate body 1121 and inserted into the upper plate member 1110.

The at least one first elastic protrusion 1123 a is provided in theupper end portion 1123 and is locked to the corresponding first lockingslot 1115 a formed in the vertical extension panel 1115, thus fasteningthe side plate body 1121 to the upper plate member 1110. To achievethis, the side plate body 1121 may be configured such that a proximalend thereof extends downwards from the side plate body 1121, andopposite side edges and a distal end thereof are separated from the sideplate body 1121. Particularly, a hook which is removably locked to thecorresponding locking slot 1115 a is provided on the outer surface ofthe distal end of the first elastic protrusion 1123 a.

The lower end portion 1122 is an upright surface which is provided inthe lower end of the side plate body 1121. The lower edge of the lowerend portion 1122 is seated onto the bottom of the lower plate member1130, and the outer surface of the lower end portion 1122 is broughtinto close contact with the inner surface of the lower plate member1130.

The second elastic protrusion 1122 a is provided in the lower endportion 1122 and is locked to a corresponding one of the second lockingslots 1131 a that are formed in the inner surfaces of the sidewalls ofthe lower plate member 1130, thus fastening the side plate member 1120to the lower plate member 1130. The second elastic protrusion 1122 a isoriented in a direction opposite that of the first elastic protrusion1123 a. For example, in this embodiment, the second elastic protrusion1122 a is configured such that a proximal end thereof extends upwardsfrom the lower end portion 1122 of the side plate body 1121, andopposite side edges and a distal end thereof are separated from thelower end portion 1122. In the same manner, a hook is also provided onthe outer surface of the distal end of the second elastic protrusion1122 a. The hook of the second elastic protrusion 1122 a is removablylocked to the corresponding second locking slot 1131 a of the lowerplate member 1130.

The heat dissipation slot 1124 includes a plurality of heat dissipationslots which are formed in each side plate body 1121 and each of whichhorizontally extends a predetermined length. The heat dissipation slots1124 function to dissipate heat generated by the battery module 2000 tothe outside.

In this embodiment, two side plate members 1120 which have the samestructure are provided. The first side plate body 1121 which is disposedat a first side and the second side plate body 1121′ which is disposedat a second side have the same shape, and each of the first and secondside plate bodies 1121 and 1121′ has the upper end portion 1123, 1123′and the to lower end portion 1122, 1122′ at the same positions. Thefirst elastic protrusions 1123 a and 1123 a′ are oriented in the samedirection, and the second elastic protrusions 1122 a and 1122 a′ arealso oriented in the same direction.

However, the first side plate body 1121 includes fastening bars 1126which are disposed at opposite ends of the surface of the first sideplate body 1121 that faces the second side plate body 1121′. Thefastening bars 1126 come into close contact with the front surface of afrontmost bare cell 2220″ of the battery module 2000 that is disposedbetween the first side plate body 1121 and the second side plate body1121, thus supporting the battery module 2000. On the other hand, thesecond side plate body 1121′ includes insert protrusions 1125 whichprotrude from opposite ends of the inner surface of the second sideplate body 1121′ towards the first side plate body 1121. The insertprotrusions 1125 are coupled into corresponding coupling holes (2212 b,refer to FIGS. 15 through 17) of a rearmost cell case so that a barecell 2220′″ that is disposed between the second side plate body 1121′and the rearmost cell case can be supported therebetween.

As such, the insert protrusions 1125 that are provided on the surface ofthe second side plate body 1121′ are inserted into the correspondingcoupling holes 2212 b which are formed in the opposite ends of a cellcase 2210 which will be explained later, thus coupling the battery cellto the second side plate body 1121′.

The lower plate member 1130 includes a bottom plate 1132; side panels1131 which are provided upright on the left and right side edges of thebottom plate 1132; the second locking slots 1131 a which are formed inthe inner surfaces of the side panels 1131 with which the lower endportions 1122 of the side plate members 1120 are brought into closecontact; and a front panel and a rear panel which are respectivelyprovided upright on the front and rear ends of the bottom plate 1132.

The bottom plate 1132 is a planar plate, and the battery module 2000 andthe lower end portions 1122 of the side plate bodies 1121 are seatedonto the bottom plate 1132.

The side panels 1131 are provided upright on the opposite side edges ofthe bottom to plate 1132. The lower end portions 1122 of the side platebodies 1121 are inserted into the lower plate member 1130 and arebrought into close contact with the inner surfaces of the correspondingside panels 1131.

The bottom end panels 1133 are provided upright on the front and rearends of the bottom plate 1132. The upper ends of the bottom end panels1133 are continuous with the upper ends of the side panels 1131, and theupper ends of the side panel 1131 are higher than those of the bottomend panels 1133. Hence, an inclined portion 1134 is formed between theupper end of each side panel 1131 and the upper end of each of thebottom end panels 1133.

At least one second locking slot 1131 a is formed in each side panel1131. When the side plate members 1120 are inserted into the lower platemember 1130, the hooks provided on the ends of the second elasticprotrusions 1122 a of the side plate members 1120 are inserted into andhooked to the corresponding second locking slots 1131 a of the sidepanels 1131.

In the battery module 2000, pouch type bare cells 2220, 2220′, 2220″,2220′″ are respectively seated onto a respective front surface 2211 band a respective rear surface 2211 a of a cell case 2210. Several ofthese bare cells 2220, 2220′, 2220″ and 2220′″ are electricallyconnected to each other. Particularly, this embodiment of the presentinvention is characterized in that the bare cells 2220, 2220′, 2220″ and2220′″ and the cell cases 2210 alternate with each other to form thebattery module, and the outermost bare cells 2220″ and 2220′″ of thebattery module are respectively supported by the inner surfaces of theside plate bodies 1121 and 1121′.

For instance, in the conventional technique, to produce a battery of 100A, four 25 A bare cells and eight cell cases that support the front andrear surfaces of the four bare cells were required.

However, in this embodiment of the present invention, because the sideplate bodies 1121 and 1121′ respectively support the frontmost bare cell2220″ and the rearmost bare cell 2220′″, only three cell cases areneeded to produce a battery that outputs 100A. This cell case will beexplained with reference to FIGS. 15 through 17.

FIG. 15 is a front perspective view of the cell case of the lithiumbattery according to an embodiment of the present invention. FIG. 16 isan exploded perspective view showing the battery cell of the lithiumbattery according to an embodiment of the present invention. FIG. 17 isa rear perspective view of the cell case of the lithium batteryaccording to an embodiment of the present invention.

Referring to FIGS. 15 through 17, in the battery module 2000 accordingto an embodiment of the present invention, at least one cell case 2210and two or more bare cells 2220˜2220′″ are alternately coupled to eachother. The side plate bodies 1121 and 1121′ respectively support thefrontmost bare cell 2220″ and the rearmost bare cell 2220′″ of thebattery module 2000.

For instance, if the output of the battery module 2000 is 50 A, thebattery module 2000 includes a first cell case 2210, the front surfaceof which receives a first bare cell 2220, and the rear surface of whichcontains a second bare cell 2220′.

In this case, the first bare cell 2220 and the second bare cell 2220′are supported by the first cell case 2210, the first side plate body1121 and the second side plate body 1121′.

If the output of the battery module 2000 is 100 A, the battery module2000 includes four 25 A bare cells and three cell cases. In detail, thebattery module 2000 includes: a first cell case 2210 which receives afirst bare cell 2220; a second cell case 2210′ which is brought intoclose contact with a rear surface of the first bare cell 2220, andreceives a second bare cell 2220′; and a third cell case 2210″ which isbrought into close contact with a rear surface of the second bare cell2220′, and receives a third bare cell 2220″.

Further, in this battery module 2000, the third bare cell 2220″ isdisposed between the inner surface of the first side plate body 2212 andthe front surface of the first cell case 2210, and a fourth bare cell2220′″ is interposed between the inner surface of the second side platebody 1121′ and the rear surface of the third cell case 2210″.

This structure of the battery module 2000 can be realized because thefront surface 2211 a and the rear surface 2211 b of the cell case 2210,along with the adjacent cell cases and 2210″, support the bare cells2220′ and 2220″ and because the side plate bodies function as the cellcases. Hereinafter, the structure of each cell case 2210 will beexplained in more detail.

The cell case 2210 includes a case body 2211, coupling protrusions 2125,coupling holes 2212 b, circuit board support protrusions 2214, tabguides 2215, a heat dissipation window 2216, a support bar 2217,horizontal support frames 2218 and partition ribs 2219. The case body2211 has the front surface 2211 a and the rear surface 2211 b. Thecoupling protrusions 2125 protrude forwards from the opposite ends ofthe front surface 2211 a of the case body 2211. The coupling holes 2212b are formed in respective portions that protrude rearwards from theopposite ends of the rear surface 2211 b of the case body 2211. Thecircuit board support protrusions 2214 protrude upwards from theopposite ends of an upper horizontal frame 2211 c that is provided inthe upper end of the case body 2211. The tab guides 2215 protrudeupwards from the upper horizontal frame 2211 c of the case body 2211 toguide the corresponding battery tabs 221 of the bare cell 220. The heatdissipation window 2216 is formed through the case body 2211. Thesupport bar 2217 is vertically provided in the medial portion of theheat dissipation window 2216 to support both bare cells 2220 that aredisposed on opposite sides of the cell case 2210. The horizontal supportframes 2218 are provided in the case body 2211 and form planar surfaceson upper and lower edges of the heat dissipation window 2216. Thepartition ribs 2219 protrude from the front surface 2211 a and the rearsurface 2211 b of the case body 2211 forwards and rearwards.

The case body 2211 has the rear surface 2211 b onto which the frontsurface of the bare cell 220 is seated, and the front surface 2211 awhich is brought into close contact with the rear surface of anotherbare cell. The case body 2211 includes the upper and lower horizontalframes 2211 c which horizontally extend on the upper and lower edges ofthe case body 2211, and vertical side frames 2211 d which verticallyextend on opposite ends of the case body 2211. As such, in the case body2211, spaces which receive the bare cells 2220 are formed on the frontsurface 2211 a and the rear surface 2211 b by the upper and lowerhorizontal frames 2211 c and the vertical side frames 2211 d.

The coupling protrusions 2125 are provided on the front surface of thecase body 2211 at opposite sides of the bare cell 2220 so that thecoupling protrusions 2125 can be inserted into the respective couplingholes 2212 b of an adjacent cell case.

The coupling holes 2212 b are formed in the rear surface of the casebody 2211 at opposite sides of the bare cell 2220 so that the couplingprotrusions 2125 of an adjacent cell case or the insert protrusions ofthe second side plate body 1121 are inserted into the respectivecoupling holes 2212 b.

The tab guides 2215 and 2215′ protrude upwards from the front and rearedges of the upper horizontal frame that horizontally extends from theupper end of the case body 2211. In detail, the two tab guides 2215 areprovided on the front surface 2211 a of the case body 2211 at positionsspaced apart from each other. The two tab guides 2215′ are provided onthe rear surface 2211 b of the case body 2211 at positions spaced apartfrom each other.

The tab guides 2215 and 2215′ form depressions through which the batterytabs of the two bare cells 2220 that are seated onto the front surface2211 a and the rear surface 2211 b of the cell case 2210 protrudeupwards from the cell case 2210. To achieve this, each tab guide 2215,2215′ may protrude upwards from a portion of the upper horizontal framethat surrounds the corresponding depression formed in the upperhorizontal frame, thus forming a space into which the correspondingbattery tab is inserted.

The circuit board support protrusions 2214 protrude upwards from theopposite ends of the upper horizontal frame of the case body 2211 andsupport a circuit board. Each circuit board support protrusion 2214includes two rods 2214 b which are provided at positions spaced apartfrom each other by a predetermined distance. In an embodiment of thepresent invention, a triangular hook 2214 a which has a downwardlyinclined surface is provided on an upper end of each of the rods 2214 bwhich are separated from each other.

In this structure, when the triangular hooks 2214 a pass through acorresponding hole of the circuit board (not shown) that has a smalldiameter, the two rods that are separated from each other approach eachother. After the triangular hooks 2214 a have passed through the hole ofthe circuit board, the two rods are moved away from each other again bythe elastic force so that the triangular hooks 2214 a can be hooked toan upper surface (not shown) of the circuit board.

The heat dissipation window 2216 is formed in the case body 2211 todissipate heat generated by the bare cells 2220 that are placed on thecase body 2211.

The horizontal support frames 2218 are surfaces that horizontally extendon the upper and lower edges of the heat dissipation window 2216 formedin the case body 2211. In an embodiment of the present invention, thehorizontal support frames 2218 have horizontal surfaces so that the barecells 2220 that are seated onto the front and rear surfaces 2211 a and2211 b of the case body 2211 are seated onto the horizontal surfaces ofthe horizontal support frames 2218.

The support bar 2217 is provided upright in a medial portion of the heatdissipation window 2216. The support bar 2217 is disposed at the medialportions of the horizontal support frames 2218 and partitions the barecell 2220, which is brought into close contact with the front surface2211 a of the cell case 2210, from the bare cell 2220 which is broughtinto close contact with the rear surface 2211 b of the cell case 2210.

The partition ribs 2219 include a plurality of vertical partition ribs2219 b which vertically extend on the front and rear surfaces 2211 a and2211 b of the case body 2211, and a plurality of horizontal partitionribs 2219 a which horizontally extend from the front and rear surfaces2211 a and 2211 b. The vertical partition ribs 2219 b and the horizontalpartition ribs 2219 a that are provided on the front and rear surfaces2211 a and 2211 b of the case body 2211 reinforce the case body 2211when the cell case 2210 is coupled to other cell case 2210. In addition,the vertical partition ribs 2219 b and the horizontal partition ribs2219 a function to form a plurality of air flow passages between theadjacent cell cases.

In this embodiment, the main body of the first bare cell 2220 whichincludes the battery tabs 2221 spaced apart from each other is seatedonto the heat dissipation window 2216 on the rear surface 2211 b of thefirst cell case. Here, the battery tabs 2211 of the first bare cell 2220are seated into the corresponding tab guides 2215 while the main body ofthe first bare cell to 2220 is seated onto the heat dissipation window2216 and onto the horizontal support frames 2218. Furthermore, the firstbare cell 2220 is supported by the support bar 2217 which is verticallyprovided in the medial portion of the heat dissipation window 2216.

The horizontal support frames 2218 are partitioned into two areas by thesupport bar 2217. That is, the support bar 2217 partitions thehorizontal support frames 2218 into an area on which the bare cell thatis seated onto the rear surface 2211 b of the case body 2211 is placed,and an area onto which the bare cell that is seated onto the frontsurface 2211 a of the case body 2211 is placed.

As such, a single battery cell includes the two bare cells that areprovided on the front and rear surfaces of the cell case. For example,if a lithium battery of 100 A is required, the battery module may havefour 25 A bare cells and be installed in the battery case.

For this, among the first through fourth bare cells 2220, the first barecell 2220 is seated onto the rear surface 2211 b of the first cell case2210. Subsequently, the second cell case 2210′ is coupled to the firstcell case 2210 in such a way that the coupling protrusions 2125 of thesecond cell case 2210′ are fitted into the coupling holes 2212 b of thefirst cell case 2210 while the front surface 2211 a of the second cellcase 2210′ is brought into close contact with the rear surface of thefirst bare cell 2220.

In the same manner, after the second bare cell 2220′ has been seatedonto the rear surface 2211 b of the second cell case 2210′, the thirdcell case 2210″ is coupled to the second cell case 2210′ in such a waythat the coupling protrusions 2125 of the third cell case 2210″ arefitted into the coupling holes 2212 b of the second cell case 2210′while the front surface 2211 a of the third cell case 2210″ is broughtinto close contact with the rear surface of the second bare cell 2220′.

Thereafter, the third bare cell 2220″ is seated onto the front surfaceof the first cell case 2210, and the fourth bare cell 2220′″ is seatedonto the rear surface of the third cell case 2210″. Subsequently, thethird and fourth bare cells 2220″ and 2220′″ are brought into closecontact with the inner surface of the corresponding side plate bodies.

Here, the insert protrusions 1125 that protrude from the second sideplate body 1121′ are fitted into the corresponding coupling holes 2212 bof the third cell case 2210″ that is disposed at the frontmost position.Thereby, the fourth bare cell 2220″ is fixed between the second sideplate body 1121′ and the third cell case 2210″. In the same manner, thethird bare cell 2220″ is fixed between the first cell case 2210 and thefirst side plate body 1121.

As such, in the present invention, for example, if a lithium battery,the output of which is 100 A, is required, four 25 A bare cells andthree cell cases are used. If a lithium battery having the output of 50A is required, two 25 A bare cells and a single cell case are used toform a battery module. Therefore, the number of cell cases can bereduced compared to that of the conventional technique. The reduction inthe number of cell cases can result in a reduction of the size of theentire lithium battery.

FIG. 18 is a perspective view illustrating a process of connectingseveral lithium batteries to each other according to an embodiment ofthe present invention.

Referring to FIG. 18, a user may use a single lithium battery to be usedat home or for portable use. If an amount of power greater than theamount of power output from the single lithium battery is required, twoor more lithium batteries can be electrically connected to each other sothat the desired amount of power can be produced.

To reduce an area required by the connected batteries and prevent anaccident from being caused by the contact with a peripheral pedestrianor from being caused by other surrounding conditions, it is necessary tomechanically connect the lithium batteries to each other.

For this, the locking protrusion 1113 a which is provided under thelower surface of the connection plate 1113 of a first battery case 1100a is fitted into the connection hole 1112 a which is formed in the uppersurface of the upper plate member that is accessible through the openslot 1112 of a second battery case 1100 b. The locking protrusion 1113 amay have a downwardly inclined surface so that it can be hooked to theconnection hole 1112 a.

After the first battery case 1100 a and the second battery case 1100 bhave been coupled to each other, the connection plate 1113 of the secondbattery case 1100 b is coupled to the connection hole 1112 a of a thirdbattery case 1100 c. As such, several battery cases can be coupled toeach other.

As described above, in embodiments of the present invention, a lithiumbattery which contains two or more battery cells has a structure thatcan be separably coupled to another lithium battery in an insertcoupling manner. Therefore, several lithium batteries can be connectedto each other, and the connected state can be reliably maintained. Inaddition, when it is necessary to separate the lithium batteries fromeach other, they can be easily separated. Thus, the convenience andsafety of use can be enhanced.

Furthermore, in the lithium battery of the embodiments of the presentinvention, battery cells can be coupled to each other in an insertcoupling manner, for example, in a such a way that a front case plate ofa battery cell is inserted into a rear case plate of an adjacent batterycell, without using a separate locking member or coupling device.Therefore, the number of assembly processes and the working time can bereduced, and the size of the lithium battery can also be reduced.

Moreover, in the embodiments of the present invention, a battery casewhich contains one or more battery cells can function as a cell casethat supports the bare cells. Therefore, the size of the lithium batterycan be further reduced. In addition, because the number of elements isreduced, the production cost can also be reduced.

Although the exemplary embodiments of the present invention have beendisclosed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas disclosed in the accompanying claims.

What is claimed is:
 1. A lithium battery comprising: a battery modulehaving battery cells electrically connected to each other such thatpower of different poles is input into or output from the battery cells;an upper plate member forming an upper surface of the lithium battery,the upper plate member covering an upper end of the battery modulecontained in the lithium battery; a lower plate member forming a bottomplate of a space that contains the battery module therein; and a pair ofside plate members placed upright and facing each other, the side platemembers being coupled at upper ends thereof to the upper plate memberand coupled at lower ends thereof to the lower plate member, wherein theupper plate member comprises: a connection plate extending from a topsurface of the upper plate member in one direction, with a lockingprotrusion formed under a lower surface of the connection plate; an openslot formed in the top surface at a position opposite to the connectionplate, the open slot having a shape corresponding to a distal end of theconnection plate; and a connection hole formed inside the open slot sothat, when the lithium battery is connected to another lithium battery,the locking protrusion of the connection plate of the lithium battery isremovably locked into the connection hole of said another lithiumbattery.
 2. The lithium battery as set forth in claim 1, wherein theupper plate member comprises vertical extension panels extending fromopposite side edges of the top surface, the vertical extension panelscomprised of a first vertical extension panel and a second extensionpanel facing each other, and each of the first and second extensionpanels has at least one first locking slot; the lower plate membercomprises side panels vertically protruding upwards from opposite sideedges of the bottom plate, the side panels comprised of a first sidepanel and a second side panel facing each other, and each of the firstand second side panels has at least one second locking slot; and each ofthe side plate members comprises: a first elastic protrusion provided onan upper end of the side plate member, the first elastic protrusionbeing locked to one of the first locking slots formed in the first andsecond vertical extension panels; and a second elastic protrusionprovided on a lower end of the side plate member, the second elasticprotrusion being locked to one of the second locking slots formed in thefirst and second side panels.
 3. The lithium battery as set forth inclaim 1, wherein each of the side plate members comprises a side platebody coupled at an upper end thereof to the upper plate member andcoupled at a lower end thereof to the lower plate member, and thebattery module comprises at least one battery cell having a cell caseand bare cells provided on front and rear surfaces of the cell case suchthat the cell case and the bare cells alternate with each other, whereinone side surface of each of outermost bare cells is supported by thefront or rear surface of the cell case, and a remaining side surface ofthe outermost bare cell is supported by an inner surface of one of theside plate bodies.
 4. The lithium battery as set forth in claim 2,wherein the first elastic protrusion has a hook on a distal end of thefirst elastic protrusion, and the hook is locked into the first lockingslot; and the second elastic protrusion has a hook on a distal end ofthe second elastic protrusion, and the hook is locked into the secondlocking slot.
 5. The lithium battery as set forth in claim 1, whereineach of the battery cells comprises a cell case containing pouch typebare cells, the cell case comprising: a case body placed upright andreceiving the bare cells, the cell case having an upper horizontal frameand a lower horizontal frame respectively provided on upper and loweredges of the case body, and vertical side frames extending betweenopposite ends of the upper and lower horizontal frames; a couplingprotrusion protruding from a first surface of the case body in onedirection; and a coupling hole formed in a second surface of the casebody so that the coupling protrusion of another cell case is insertedinto the coupling hole.
 6. The lithium battery as set forth in claim 5,wherein either of the side plate members further comprises an insertprotrusion provided on at least one surface thereof that faces thebattery module contained in the lithium battery, the insert protrusionbeing inserted into the coupling hole of the cell case.
 7. The lithiumbattery as set forth in claim 5, wherein the cell case comprises: tabguides protruding upwards from an upper end of the case body, whereinthe tab guides comprise: a pair of tab guides disposed at a sidecorresponding to a front surface of the case body at positions spacedapart from each other; and a pair of tab guides disposed at a sidecorresponding to a rear surface of the case body at positions spacedapart from each other.
 8. The lithium battery as set forth in claim 5,wherein the cell case further comprises a circuit board supportprotrusion protruding upwards from the upper horizontal frame that formsan upper surface of the case body, the circuit board support protrusionsupporting a circuit board, wherein the circuit board support protrusioncomprises two rods spaced apart from each other, with a hook protrudingfrom an upper end of each of the two rods, the hook having a downwardlyinclined surface.
 9. The lithium battery as set forth in claim 5,wherein the cell case further comprises: a heat dissipation windowformed in the case body to dissipate heat generated by the bare cells;horizontal support frames provided in the case body and forming planarsurfaces extending in the horizontal direction on upper and lower edgesof the heat dissipation window so that the bare cells are respectivelyseated onto the front and rear surfaces of the case body; and a supportbar vertically provided in a medial portion of the heat dissipationwindow and fastened to the horizontal support frames.
 10. The lithiumbattery as set forth in claim 5, wherein the cell case furthercomprises: a plurality of vertical partition ribs provided on the frontand rear surfaces of the case body, each of the vertical partition ribsextending a predetermined length vertically; and a plurality ofhorizontal partition ribs provided on the front and rear surfaces of thecase body, each of the horizontal partition ribs extending apredetermined length horizontally.
 11. The lithium battery as set forthin claim 1, wherein each of the side plate members further comprises aplurality of heat dissipation slots formed to dissipate heat generatedby the battery module.